To all those that say, 'use the search bar' every time someone renews this perennial classic, the 'scariest-games-ever' thread, I say, enough. What's wrong with re-posting old threads as long as it is done with pacing and it isn't done in excess? It gives people opportunities to post about new games that have been scaring the pants off them and gives others the opportunity to weigh in about the scariest games ever if they missed the old thread.
But as for me, my choices for scariest game ever include:
1. Condemned: Criminal Origins and Condemned 2: Bloodshot.
2. Resident Evil 4 and 5.
3. F.E.A.R. 2, which was scary at times, despite its mediocrity.
4. Dead Space.
5. Bioshock.